Abstract

A common source of error in particle tracking experiments is identified, and a theoreticalmodel for the magnitude of the error is offered. In many cases, the error is small, but in systems where only a few particles are being tracked, the measured mean squared displacement can be up to 50% smaller than the actual value. The theoreticalmodel predictions are confirmed using numerical simulations and experimental observations of polystyrene microspheres in water.

Received 24 September 2012Accepted 03 January 2013Published online 17 January 2013

Acknowledgments:

P. T. C. So acknowledges support from NIH 9P41EB015871-26A1, R01-EX017656, 5 R01 NS051320, 4R44EB012415-02, and NSF CBET-0939511, the Singapore-MIT Alliance 2, the BioSym IRG of Singapore-MIT Alliance Research and Technology Center, and the MIT SkolTech initiative. C.J.R. is grateful for a Wellcome Trust MIT Postdoctoral Research Fellowship to carry out this research; this work was supported by the Wellcome Trust 093831/Z/10/Z. The authors are both grateful to Dr. Adam Corrigan for providing his matlab code and for his many fruitful discussions over email.